The present invention relates to sensors for determining an objects position relative to a reference structure.
Advanced safety restraint systems such as inflatable air bags and pyrotechnic seatbelt restraint systems are in wide spread use in vehicles today. Generally, these advanced restraint systems deploy during a serious vehicle collision, preventing the vehicle occupants from colliding with the vehicle""s interior.
Typically, air bag systems are comprised of vehicle crash sensors which detect a vehicle collision, air bag inflators which inflate the air bag, and an air bag cushion which receives a vehicle occupant. Typically, advanced seat belt restraint systems are comprised of pyrotechnic retractors. The pyrotechnic retractors quickly retract the seat belt webbing using an explosive charge, as well known in the art. Other seat belt components such as load limits prevent excessive loading on the occupants chest by releasing tension on the seat belt webbing.
Although these vehicle restraint systems have significantly reduced vehicle occupant injuries problems still exist. For example, when vehicle occupants are xe2x80x9cout of positionxe2x80x9d that is too close to a deploying air bag the vehicle restraint systems are not as effective at reducing occupant injuries. More advanced inflatable restrain systems are available which decrease air bag inflation forces when vehicle occupants are determined to be too close to the inflating air bag. However, occupant positioning sensors that measure an occupant""s proximity to an inflating air bag are expensive to implement and have questionable accuracy.
Therefore, what is needed is low cost sensing system for estimating vehicle occupant proximity to an inflatable restraint system for modifying the inflatable restraint system in accordance with occupant position.
Accordingly, a sensor system for determining a relative position of a vehicle seat, wherein the vehicle seat is fixed to a vehicle floor by a seat track, and the seat track has an upper seat track portion connected to the vehicle seat and a seat track lower portion connected to a vehicle floor, is provided. The sensor system has a sensing element affixed to one of the upper seat tack portion and the lower seat track portion, at lease one receiver element in communication with the sensing element. An enabler is disposed adjacent to the other of the upper seat track and the lower seat track. The enabler has at least one activation zone for causing the sensing element to communicate with the at least one receiver element. At least one deactivation zone is provided for preventing the sensing element from communicating with the at least one receiver element. The at least one activation zone defines at least one position of the vehicle seat and the at least one deactivation zone defines at least one other position of the vehicle seat.
In an embodiment of the present invention a wiper for cleaning the sensing element of debris is provided.
In another embodiment of the present invention the wiper is a resilient material.
In still another embodiment of the present invention the sensing element is an electro-luminescent component.
In still another embodiment of the present invention the electro-luminescent component is a light emitting diode.
In still another embodiment of the present invention the electro-luminescent component is an incandescent light source.
In still another embodiment of the present invention the at least one receiver element is an optical receiver.
In still another embodiment of the present invention the optical receiver is a phototransistor.
In still another embodiment of the present invention the sensing element is a magnet.
In still another embodiment of the present invention the at least one receiver element is a hall effect sensor.
In still another embodiment of the present invention the sensing element is a lever portion of a mechanical switch.
In still another embodiment of the present invention the at least one receiver element is a plunger portion of a mechanical switch.
In still another embodiment of the present invention a sensor housing for holding the sensing element opposite the at least one receiver element is provided.
In still another embodiment of the present invention the sensor housing has at least two downwardly extending side walls.
In still another embodiment of the present invention the sensing element is fixed to one of the at least two side walls and the at least one receiver element is fixed opposite the sensing element to another of the at least two side walls.
In still another embodiment of the present invention the at least two downwardly extending side walls define a longitudinally extending u-channel in the sensor housing.
In still another embodiment of the present invention the at least one activation zone is a longitudinally extending slot.
In still another embodiment of the present invention the at least one deactivation zone is a longitudinally extending opaque area.
In still another embodiment of the present invention the at least one activation zone is a longitudinally extending magnetic material.
In still another embodiment of the present invention the at least one deactivation zone is a longitudinally extending non-magnetic area.
In still another embodiment of the present invention the sensing element is disposed adjacent the at least one receiver element.
In still another embodiment of the present invention a sensor housing having at least one downwardly extending side wall.
In still another embodiment of the present invention the at least one activation zone is a longitudinally extending light reflecting area.
In still another embodiment of the present invention the at least one deactivation zone is a longitudinally extending light non-reflecting area.
In still another embodiment of the present invention the at least one activation zone is a longitudinally extending electrically conductive area.
In still another embodiment of the present invention the at least one deactivation zone is a longitudinally extending non-electrically conductive area.
In yet another embodiment of the present invention a sensor system for measuring a relative position of a vehicle seat, wherein the vehicle seat is fixed to a vehicle floor by a seat track, the seat tack has an upper seat track portion connected to the vehicle seat and a seat track lower portion connected to a vehicle floor. The sensor system includes a sensing element affixed to one of the upper seat tack portion and the lower seat track portion, a plurality of receiver elements are in communication with the sensing element. An enabler is disposed adjacent to the other of the upper seat track and the lower seat track. The enabler has a plurality of activation zones for causing the sensing element to communicate with the plurality of receiver elements, and a plurality of deactivation zones which prevent the sensing element from communicating with the plurality of receiver elements.
The above features, benefits and advantages and other features, benefits and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken together with the accompanying drawings.